Parachute cluster spacing means



Jan. 2, 1951- v P. F. SMITH 2,536,777

. PARACHUTE CLUSTER SPACING MEANS Filed Dec. 17, 1945 Fig.1 F1911 Fig. Fig. 1E

INVENTOR.

Patented Jan. 2, 1951 UNITED STATES PATENT OF F jl-CE assemn "PARACHUTE OEUS TER- SPAC-ING*MEAN S iBremstRzSmith, San-.Ili gmrQal Applicatiqnflecemher 17, 11945,;SerialNo. 635,473

This parachute cluster spacing means relates broadly to a way in which the resistance of a cluster of parachutes through the air can be greatly increased, even doubled or more than :doubled, over the-resistance 'of either the same number of parachutes acting individually..as.in the ordinary sense of a cluster of parachutes or acting together as a single solid unit as is often employed. To be "more specific, in some -designs, all the parachutes are anchored {-to the same object, but otherwise they are not connected to-each other. -Onthe'other hand-some designs attach the skirts of the parachutes togetherso that in either casethe maximum drag .isnotachieved.

"Now in "my invention the parachutes are attached to the same cargo as in the others, but are also attached to each other with flexible connecting means such as a piece of 500 pound cord whose length is preferably a third or a fourth of the projected diameter of one of the parachutes. The interference of the air between the parachutes causes them to try to separate thereby pulling on the connecting cord.

My tests have shown this interference drag between the parachutes causes the overall drag to double, for a given speed. Also the parachutes, in trying to separate, pull on the skirts thereby increasing the projected area, producing more drag.

There are a number of different combinations of parachutes that can be attached together in this manner. The smallest cluster would be two parachutes with a single connecting cord. Then three parachutes with three connecting lines or also a central point with the three cords radiating to each of the three parachutes. chutes would have either of the two methods of attaching the cords. When five or more parachutes are used, further tests may show a single parachute in the center with the other parachutes around it to be most effective. The connecting cords then could be either from the skirt of the center parachute to each of the outer ones or merely between the peripheries of the outer ones. Perhaps both methods together will produce the most drag. In all cases, the connecting cord will be a third to a fourth of the projected diameter of the parachutes.

The size and number of parachutes used in a cluster of parachutes is dependent upon the use that the system will be subjected to. Small parachutes open fast. Big parachutes open slow. So if conditions call for low altitude and low speed, then a larger number of smaller para- Four para-.

chutes must be used. For reasonable altitudes at higher speeds, larger parachutesbutsmallerzin I -number-are-necessary.

Therefore I do not wish to be limited to .a

-Figures l through XI are plan views showing :the forms :thatII willmost. generallyuse in which thevparachutes, .are connected together bythe connecting cords.. 2, .while Fig. XIIisa sideview supporting an .'airplane,3, with lift .webs,..4. :Having thus described my invention, whatI claim -as-new and desireto. secure. by Letters Patent is:

1. In a parachute cluster spacing means of the class described the combination of a plurality of parachutes substantially spaced apart equal to ten per cent or more of the diameter of said parachutes, attachments in connection with each parachute adapted to be connected with a common cargo, connectors for said parachutes secured to the peripheries thereof and extending directly intermediate each other on a common plane with the substantially spaced edges of said parachute at said peripheries.

2. In -a parachute cluster spacing means of the class described the combination of a plurality of parachutes substantially spaced apart equal to ten per cent or more of the diameter of said parachutes, attachments in connection with each parachute adapted to be connected with a common cargo, connectors for said parachutes secured to the peripheries thereof and extending directly intermediate each other on a common plane with the substantially spaced edges of said parachute at said peripheries, and said connecting means consisting of broad straps sewed to the peripheries-of said parachutes.

3. In a spacing means for cluster parachutes, the combination of a plurality of substantially spaced parachutes having attachment cords of equal length adapted to be connected to a common cargo, connecting means for said parachutes disposed on a horizontal plane intercon necting the peripheral lower edges of said parachutes substantially spaced apart equal to ten per cent or more of the diameter of said parachutes whereby said parachutes are restrained radially accomplishing substantially spaced disposition of said parachutes when in operation.

4. In a spacing means for cluster parachutes, the combination of a plurality of substantially spaced parachutes having attachment cords of equal length adapted to be connected to a common cargo, connecting means for said parachutes disposed on a horizontal plane interconnecting the peripheral lower edges of said parachutes substantially spaced apart equal to ten per cent or more of the diameter of said parachutes whereby said parachutes are restrained radially accomplishing substantially spaced disposition of said parachutes when in operation, and said connecting means including tapes sewed to the peripheries of said parachutes.

5. In a parachute cluster spacing means of the class described the combination of a plurality of parachutes arranged in a cluster having a centrally disposed parachute, connecting means secured to said centrally disposed parachute and extending radially into connected relation with the surrounding parachutes, said connecting means secured at the peripheral edge of said centrally disposed parachute and extending on a horizontal plane to the lower peripheral edges of said surrounding parachutes.

6. In a parachute cluster spacing means of the class described the combination of a plurality of parachutes arranged in a cluster having a centrally disposed parachute, connecting means secured to said centrally disposed parachute and extending radially into connected relation with the surrounding parachutes, said connecting means secured at the peripheral edge of said centrally disposed parachute and extending on a horizontal plane to the lower peripheral edges of said surrounding parachutes, and second connecting means interconnecting the surrounding parachutes outwardly of said centrally disposed parachute, said second connecting means posi- 4 tioned on a horizontal plane substantially at the lower edges of said surrounding parachutes.

'7, In a parachute cluster spacing means of the class described the combination of a plurality of parachutes arranged in a cluster having a centrally disposed parachute, connecting means secured to said centrally disposed parachute and extending radially into connected relation with the surrounding parachutes, said connecting means secured at the peripheral edge of said centrally disposed parachute and extending on a horizontal plane to the lower peripheral edges of said surrounding parachutes, and second connecting means interconnecting the surrounding parachutes outwardly of said centrally disposed parachute, said second connecting means positioned ona horizontal plane substantially at the lower edges of said surrounding parachutes, and

attachment cords in connection with all of said parachutes adapted to be connected to a common cargo.

PREVOST F. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,394,201 Lemon Oct. 18, 1921 1,782,134 Coplen Nov. 18, 1930 2,048,159 Hoffman July 21, 1936 FOREIGN PATENTS Number Country Date 379,886 Italy Apr. 11, 1940 

